Esters of oxypropylated oxyalkylated polypentaerythritols



Patented May 25, 1954 ESTERS F OXYPROPYLATED OXYALKYL- ATED PULYPENTAERYTHRITOLS Melvin lDe Groote, University City, Mo., assignor to Petrolite Corporation, a corporation of Delaware No Drawing. Application May 14, 1951, Serial No. 226,317

8 Claims.

The present invention is a continuation-1m part .of my co-pending applications, Serial Nos. 127,773, now U. S. Patent No. 2,552,533, and 127,774, now abandoned, both filed November 15, 1949. Said aforementioned co-pending applications represent in turn a -continuation-inpart of my co-pending applications, Serial Nos. 104,801, now U. S. Patent No. 2,552,528, and 104,802, now abandoned, both filed July 14, 1949. See also my co-pending applications, Serial Nos. 104,805, now U. S. Patent No. 2,554,667, and 104,806, now abandoned, both filed July 14, 1949.

Clo-pending application Serial No. 104,801, now U. S. Patent No. 2,552,523, may be characterized by claim 1 of said application, which is as follows:

A process for breaking petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including high molal oxypropylation derivative of monomeric polyhydric compounds with the proviso that (a) the initial polyhydric reactant be free from any radical having at least 8 uninterrupted carbon atoms; (0) the initial polyhydric reactant have a molecular weight not over 1200 and at least 4 hydroxyl radicals; (c) the initial polyhydric reactant be water-soluble and xylene-insoluble; (d) the oxypropylation end product be water-insoluble and xylene-soluble; (e) the oxypropylation end product be within the molecular weight range of 2000 to 30,000 on an average statistical basis; (1) the solubility characteristics of the oxypropylation end product in respect to water and xylene be substantially the result of the oxypropylation step; (9) the ratio of propylene oxide per hydroxyl in the initial polyhydric reactant be within the range of 7 to 70; (h) the initial polyhydric reactant represent not more than 12 by weight of the oxypropylation end product on a statistical basis, and (i) the preceding provisos being based on complete reaction involving the propylene oxide and the initial polyhydric reactant.

Claim 1 of Serial No. 104,802, filed July 14, 1949; now abandoned, is substantially the same, except that it is concerned with the high molal oxypropylation derivatives as such and not specifi-cally for demulsification.

Attention is additionally directed to the copending application of Melvin De Groote, Serial No. 127,771, filed November 16, 1949, now U. S. Patent No. 2,552,532. Briefly stated, the particular invention described in this co-pending application is concerned with the breaking of petroleum emulsions of the water-in-oil type characterized by subjecting the emulsion to the action of a demulsifier including high molal oxypropylation derivatives of oxyalkylated intermediates; said oxyalkylated intermediates being derived in turn from water-insoluble xylene-insoluble, polypentaerythritols having at least 8 hydroxyl radi cals, with the proviso that (a) the initial polyhydric reactant be free from any radical having at least 8 uninterrupted carbon atoms; (b) the intermediate have a molecular weight in excess of 1200 and less than 25,000; (0) the intermediate product be obtained by an oxypropylation step involving a member of the class consisting of ethylene oxide and glycide; (d) the intermediate product be water-dispersible, at least to the extent of colloidal solubility, and be Xylene-insoluble; (e) the solubility characteristics of the intermediate in respect to water be substantially the result of the oxyalkylation step employing a member of the class consistin of ethylene oxide and gly-cide; (7) the oxypropylation end product be within the molecular weight range of 5,000 to 100,000 on an average statistical basis; (9) the oxypropylation end product be xylene-soluble; (h) the xylene solubility characteristics of the oxypropylation end product be substantially the result of the oxypropylation step; the initial polyhydric reactant represent not more than 7% by weight of the oxypropylation end product on a statistical basis, and that (9') the preceding provisos be based on complete reaction involving the alkylene oxides and the initial polyhydric reactant.

The invention of Serial No. 127,773, filed November 16, 1949, now U. S. Patent No. 2,552,533, is differentiated from the two previously described inventions in that the initial reactant is not water-soluble, thus being distinguished from the inventions in my co-pending applications, Serial Nos. 104,801 and 104,802, now abandoned, both filed July 14, 1949; and distinguished from the invention described in my co-pending application, Serial No. 127,770, filed November 16, 1949, insofar that the initially water-insoluble material is not subjected to an intermediate step such as treatment with ethylene oxide or glycide, or both, to render it at least colloidally water-soluble. Stated another way, in the said invention the initially water-insoluble and xylene-insoluble material is treated at once with propylene oxide so as to render it Xylene-soluble.

The final oxypropylation products as described in co-pending application Serial No. 127,773, now U. S. Patent No. 2,552,533, are not only xylenesoluble but may be even water-dispersible, especially in the latter stages of oxypropylation. In the higher stages they are invariably water-insoluble and this applies particularly to the oxypropylation derivatives derived from polypentaerythritol of a molecular weight greater than that of hepta-pentaerythritol.

More specifically, then the process of Serial No. 127,773, now U. S. Patent No. 2,552,533, is concerned with treating petroleum emulsions of the water-in-oil type with the oxyprcpylation proda ucts obtained from tripentaerythritol and higher polypentaerythritols.

Similarly, co-pending application, Serial No. 127,774, now abandoned, is concerned with the compounds as such and is not specifically limited to the use as demulsifiers.

Referring to the two previously mentioned pending applications, to wit, Serial Nos. 121,773, now U. .S. Patent No. 2,552,533, and 127,774, now abandoned, both filed November 16, 1949, there appeared subject matter concerned with derivatives of such oxypropylated polyhydric compounds and which stated that such oxypropylated polyhydric compounds can be combined with a wide variety or polycarboxy acids, such as tricarballylic acid, or citric acid, but it is preferred to employ a dicarboxy acid, or acid anhydride, such as oxalic acid, maleic acid, tartaric acid, citraconic acid, phthalic acid, adipic acid, succinic acid, azelaic acid, sebacic acid, adduot acids obtained by reaction between maleic anhydride, citraconic anhydride, and butadiene, diglycollic acid or a cyclopentadiene adduct. A specific type described includes acidic fractional esters, i. e., esters having free carbonyl radicals.

Furthermore, as stated in said previously referred to subject matter, the new derivatives include among others acid esters of the kind just referred to and having the properties of the original hydroxylated compound insofar that they are effective and valuable deinulsifying agents for resolution of water-in-oi1 emulsions found in the petroleum industry, as break inducers in doctor treatment of sour crude, etc.

Dipentaerythritol is only slightly water-sob uble at ordinary temperatures, possibly in the neighborhood of about two-tenths per cent. It is not unusual to classify such materials for ordinary purposes as being sparingly soluble or insoluble for the particular purpose in mind. In other words, dipentaerythritol is in essence a borderline compound that can be classified either Way, depending on the purpose in mind. For this reason I have preferred to consider dipentaerythritol as water-insoluble in the present description and thus include it with tripentaerythritol and higher pentaerythritols. Such change involves essentially only one change in the description of the invention of Serial No. 127,773, now U. S. Patent No. 2,552,533, to wit, including polypentaerythritols that have at least 6 hydroxyl radicals. In essence, the only other change required is to take out the word waten insoluble for the reason that tripentaerythritol and higher pentaerythritols are water-insoluble and the status of dipentaerythritol, as previously pointed out, has already been noted. Other-- wise, some awkward nomenclature, such as polypentaerythritols which at the most are only sparingly water-soluble would have to be included and would add nothing to point out the invention with greater specificity. This simply means that what is said herein is also a continuationin-part of aforementioned co-pending applica tions, Serial Nos. 104,805, now U. S. Patent No. 2,554,667, and 104,806, now abandoned, both filed on July 14, 1949. These last two co-pending applications in essence were concerned with dipentaerythritol used in a matter analogous to tripentaerythritol and higher pentaerythritols previously described.

In fact, there does not seem to be anything gained by including reference to having at least 6 hydroxyls for the reason that all polypentaerythiii) ritols beginning with dipentaerythritol upward have at least 6 hydroxyls. Furthermore, they are all xylene-insoluble. With this in mind, it will be noted that the statement of the invention subsequently has been simplified. As has been pointed out previously, due to commercial availability and for other reasons, my preferred polypentaerythritols are dipentaerythritols and tripentaerythritols.

The present invention is concerned particularly with these last-mentioned previously-described acidic esters (co-pending applications Serial Nos. 127,771, new U. Patent No. 2,552,532 and 127,772, now abandoned, both filed November 16, 1949) as new compounds and which are of par ticular value as demulsifiers for water -in-oil emulsions. More specifically, the present invention is an extension insofar that it involves dipentaerythritol as well as tripentaerythritol and higher pentaerythritols by virtue that it is specifled that the intermediate derivatives of such polypentaerythritols must be at least self-emulsitying or soluble to the extent of a 1% solution in water at ordinary temperature; or, more briefly, just soluble or emulsifiable in water without specifying the temperature because this con ventionally means at a temperature of 22.5 C.. and since dipentaerythritol is soluble in water at ordinary temperature to about 2% only this particular polypentaerythritol is included. Note that the same solubility characteristics appear in my two other co-pending applications filed on this same date, to wit, Serial Nos. 225,314, new U. S. Patent No. 2,626,907, and 226,315.

More specifically then in greater detail the present invention is concerned with certain fractional esters; said fractional esters being obtained by reaction between (A) a polycarboxy acid, and (B) high molal oxypropylation derivatives of oxyallrylated intermediates; and said oxyalkylatcd intermediates being derived in turn from polypentaerythritols, with the proviso that (a') the initial polyhydric reactant be free from any radical having at least 8 uninterrupted carbon atoms; ('5) the intermediate have a molecular weight in excess of 1200 and less than 25,000; (0) the intermediate product be obtained by an oxyalkylation step involving a member of the class consisting of ethylene oxide and glycide; (d) the intermediate product be water-dispersible, at least to the extent of colloidal solubility, and be xylene-insoluble; (e) the solubility characteristics of the intermediates in respect to water be substantially the result of the oxyalkylation step employing a member of the class consisting of ethylene oxide and glycide; (j) the oxypropylation end product be Within the molecular weight range of 5,000 to 100,000 on an average statistical basis; (9) the oxypropylation end-product be at least xylene dispersible; (h) the xylene dispersibility characteristics of the oxypropylation end-product be substantially the result of the oxypropylation step; (2') the initial polyhydric reactant represent not more than 7% by weight of the oxypropylation end-product on a statistical basis, and that (9') the preceding provisos be based on complete reaction involving the alkylene oxides and the initial polyhydric reactant; and with the proviso that the ratio of (A) to (B) be one mole of the polycarboxy acid for each available hydroxyl radical.

Complementary to the above aspect of the invention herein disclosed is my companion invention concerned with the use of these particular chemical compounds, or products, as dev finishes, as lubricants,

for various purposes,

. approximately the same mulsifying agents in processes or procedures particularly adapted for preventing, breaking, or resolving emulsions of the water-in-oil type, and particularly petroleum emulsions. See my copending application, Serial No. 226,316, filed May 14, 1951, now U. S. Patent No. 2,626,908.

Although the herein described products have a number of industrial applications, they are of particular value for resolving petroleum emulsions of the water-in-oil type that are commonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion. This specific application is described and claimed in my co-pending application, Serial No. 226,316, filed May 14, 1951, now U. S. Patent No. 2,626,908.

The new products are useful as wetting, detergent and leveling agents in the laundry, textile and dyeing industries; as wetting agents and spreaders in the application of asphalt in road building and the like; as a flotation reagent in the flotation separation of various aqueous suspensions containing negatively charged particles, such as sewage, coal washing waste Water, and various trade wastes and the like; as germicides, insecticides, emulsifying agents, as, for example, for cosmetics, spray etc.

For convenience, what is said hereinafter will be divided into five parts:

Part 1 is concerned with the description of the polyhydric reactants ence to other compounds, products, etc., so there may be a clear line of demarcation between the present invention and what may appear else- Where;

Part 2 is concerned with the preparation of intermediate reactants by use of ethylene oxide or glycide, or both;

Part 3 is concerned with the preparation of the oxypropylated derivatives from the intermediates;

Part 4 is concerned with the preparation of the acidic esters by reacting the polyhydroxylated compound with polycarboxy acid; and

with derivatives valuable including demulsification but not specifically claimed in the instant application.

Part 5 is concerned PART 1 Generally speaking, organic compounds having number of oxygen atoms as carbon atoms are apt to be, and almost invariably are, water-soluble, and the most common could be illustrated by ethyl alcohol, methyl alcohol, acetic acid, acetone, formaldehyde, etc. When compounds reach enormously high molecular weights compared with such simple compounds, for instance, in the category of 30,000 to 50,000, or upward and preferably upward, such approximate ratio of carbon to oxygen does not necessarily guarantee water-solubility as, for example, in the case of cellulose or possibly some starches. There are other classes of comparatively low molecular weight compounds, for instance, polypentaerythritols, varying from tri-pentaerythritol to deca-pentaerythritol, where the molecular weight varies roughly from 372 to 1200, which are k not water-soluble in the ordinary sense.

Pentaerythritol is fairly water-soluble, approximately 4% or 5% in water at ordinary temperature. Dipentaerythritol is soluble to the extent of twotenths of one per cent and is an initial material oils, water-repellent textile employed, as well as referemployed in the process or composition described in my aforementioned co-pending applications, Serial Nos. 104,801, now U. S. Patent No. 2,552,528, and 104,802, now abandoned, both filed July 14, 1949. The higher pentaerythritols do not qualify as a raw material in the aforementioned co-pending applications for the reason they do not meet the specification as to water-solubility prior to oxypropylation.

The present invention, as has been pointed out iently as intermediates.

The acidic fractional esters owe their valuable properties, at least in part, to the inherent properties of the parent hydroxy compound or the derivatives which have been previously referred to as intermediates. These intermediate compounds herein described owe their peculiar properties to a number of factors immediately enumerated, at least in part:

(a) Size of molecule (b) Shape of molecule as far as space configuration goes (0) Absence of a single hydrophobe group having as many as 8 uninterrupted carbon atoms in a single radical (d) Substantial insolubility in water in certain instances (e) Solubility in xylene (f) The fact that the initial reactant requires the presence of at least 6 hydroxyl radicals (9) Such combination being obtained by reaction involving propylene oxide.

Molecular weight Tri-pentaerythritol 372.41 Tetra-pentaerythritol 490.54 Penta-pentaerythritol 608.67 Hexa-pentaerythritol 726.80 Hepta -pentaerythritol 844.93 Octa-pentaerythritol 963.06 N ona-pentaerythritol 1,081.19 Deea-pentaerythritol 1,199.32

Other procedures have been described for preparing polypentaerythritol, using some other catalyst as described in British Patent No. 615,370, to Marrian and McLean (Imperial Chemical Industries, Ltd).

The same-catalyst as used in the above two mentioned issued patents illustrates a class of catalyst employed also to produce etherization in numerous other polyhydric compounds as, for example, in the case of polyglycerols, sorbitol, etc., etc. It is obvious that modified polypentaerythritol can be obtained by inter-mixing with another polyhydric alcohol, even though not waterinsoluble, followed by etherization, to produce the higher molecular weight product. For instance, two moles of tripentaerythritol could be polymerized with one mole of glycol or diglycerol to give a modified hexa-pentaerythritol which, in essence, might be somewhat analogous to a hexapentaerythritol treated with glycide, although not necessarily so. Similiarly, other polyhydric alcohols, such as sorbitol, sorbitan, mannitan, manitol, and tetramethylolhexanol, can be employed, provided, however, that the resultant used as an initial reactant is water-insoluble, and xyleneinsoluble, has at least 6 hydroxyls and a molecular weight not in excess of 1200. Such materials can be varied in an inconsequential or insignificant sort of way without detracting from the structure of the final oxypropylated derivative; for instance, a number of the hydroxyl groups might be converted into an acetal or a ketal in the conventional manner; or one might produce an ester of a low molal acid, such as acetic acid, glycollic acid, lactic acid, propionic acid, etc. Tripentaerythritol could be treated with a mole of ethylene oxide or several moles of ethylene oxide, or a mole of glycide, or a mole of butylene oxide, or methyl glycide, and then subjected to polymerization so as to give materials which, obviously, are the chemical and also physicalchemical equivalent of the herein specified, preferred and commercially available reactants, i. e., the polypentaerythritols.

My preferred reactants are tripentaerythritol, which is sold commercially, and a higher polypentaerythritol (average hydroxyl content 32.3) My third preferred reactant is the tetrapentaerythritol manufactured in the manner described in Example 2 of aforementioned British Patent No. 615,370.

In a preceding paragraph reference has been made to substantial insolubility in water in certain cases. In examining the data in Part 2 of the text it will be noted that the derivatives are limited to those which show xylene-solubility and that in the higher stages of oxypropylation the derivatives show water-insolubility or substantial water-insolubility. This is illustrated by examples and, as a matter of fact, in many instances the waterinsoluble derivatives are particularly to be preferred for use as demulsifiers.

PART 2 Part 2 is concerned with the production of water-soluble derivatives from dipentaerythrit'ol or tripentaerythritol or higher polypentaerythritols by reaction with ethylene oxide or glycide, or both. Part 3 is concerned with oxypropylation. Since the equipment used for oxyethylation and oxypropylation is essentially the same insofar that an autoclave with suitable arrangements for introduction of the reactant is employed this equipment will be described in the instant part of the specification and, thus, repetition avoided in Part 3.

Similarly, although pressure is not required in the introduction of glycide the same piece of equipment can be employed, using an open condenser as will be pointed out in the text.

I have prepared derivatives of the kind described in Part 1, preceding, on a scale varying from a few hundred grams or less in the laboratory, to hundreds of pounds on a plant scale. The same applies in the preparation of the oxyalkylated compounds which are concerned with the third part of the text. In preparing a large number of examples I have found it particularly advantageous to use laboratory equipment which permits continuous oxypropylation and oxyethylation. More specific reference will be made to treatment with glycide subsequently in the text. The oxypropylation step is, of course, the same as the oxyethylation step insofar that two low boiling liquids are handled in each instance. What immediately follows refers to oxyethylation and it is understood that oxypropylation can be handled conveniently in exactly the same manner.

The oxyethylation procedure employed in the preparation of derivatives of the preceding intermediates has been uniformly the same, particularly in light of the fact that a continuous operating procedure was employed. In this particular procedure the autoclave was a conventional autoclave, made of stainless steel and having a capacity of approximately one gallon, and a working pressure of 1,000 pounds gauge pressure. The autoclave was equipped with the conventional devices and openings, such as the variable stirrer operating at speeds from 50 R. P. M. to 500 R. P. M., thermometer well and thermocouple for mechanical thermometer; emptying outlet, pressure gauge, manual vent line; charge hole for initial reactants; at least one connection for conducting the incoming alkylene oxide, such as ethylene oxide, to the bottom of the autoclave; along with suitable devices for both cooling and heating the autoclave, such as a cooling jacket and, preferably coils in addition thereto, with the jacket so arranged that it is suitable for heating with steam or cooling with water, and further equipped with electrical heating devices. Such autoclaves are, of course, in essence small scale replicas of the usual conventional autoclave used in oxyalkylation procedures.

Continuous operation, or substantially continuous operation, is achieved by the use of a separate container to hold the alkylene oxide being employed, particularly ethylene oxide. The container consists essentially of a laboratory bomb having a capacity of about one-half gallon, or somewhat in excess thereof. This bomb was equipped, also, with an inlet for charging, and an outlet tube going to the bottom of the container so as to permit discharging of alkylene oxide in the liquid phase to the autoclave. Other convenient equipment consists, of course, of the rupture disc, pressure gauge, sight feed glass, thermometer, connection for nitrogen for pressuring bomb, etc. The bomb was placed on a scale during use and the connections between the bomb and the autoclave were flexible stainless steel hose or tubing so that continuous weighings could be made without breaking or making any connections. This also applied to the nitrogen line, which was used to pressure the bomb reservoir. To the extent that it was required, any other usual conventional procedure or addition which provided greater safety was used, of course, such as safety glass, protective screens, etc.

With this particular arrangement practically all oxyethylations become uniform in that the reaction temperature could be held within a few degrees of any selected point in this particular range.

In the early stages where the concentration of i catalyst is high the temperature was generally set for around 150 C. or thereabouts. Subse quently, temperatures up to 170 C. or higher may slowed up the temperature was raised so as to speed up the reaction somewhat by use of extreme heat. If need be, cooling water was employed to control the temperature.

As previously pointed out in the case of oxypropylation as diiferentiated from oxyethylation, there was a tendency for the reaction to slow up as the temperature dropped much below the selected point of reaction, for instance, 170 C. In this instance the technique employed was the same as before, that is, either cooling water was cut down or steam was employed, or the addition of propylene oxide speeded up, or electric heat used in addition to the steam in order that the reaction proceeded at, or near, the selected temperatures to be maintained.

Inversely, if the reaction proceeded too fast regardless of the particular alkylene oxide, the amount of reactant being added, such as ethylene oxide, off, or steam was reduced, or if equipment, as has been pointed out, is conventional and, as far as I am aware, can be furnished by at least two firms who specialize in the manufacture of this kind of equipment.

Attention is directed to the fact that the use of glycide requires extreme caution. This is particularly true on any scale other than small laboratory scale Purely from the standpoint of safety in the handling of glycide, attention is directed to the following: (a) If prepared from glycerol monochlorohydrin, this product should be comparatively pure; (2;) the glycide itself should be as pure as possible as the effect of impurities are difiicult to evaluate; (c) the glycide should be introduced carefully and precaution should be taken that it reacts as promptly as introduced, i. e., that no excess of glycide is allowed to accumulate; (d) all necessary precaution should or semi-pilot plant operations.

10 should be equipped with a stainless steel cooling coil so that the pot can be cooled more rapidly than mere removal of mantle. If a stainless steel coil is introduced it means that conventional actants to mix due to swirling motion in the center of the pot. Still better is the use of a laboratory autoclave of the kind previously deshould be controlled by the usual factors, such as (a) the addition of glycide; (b) the elimination of external heat, and (0) use of cooling coil so there is no undue rise in temperature. the foregoing is merely conventional but is included due to the hazard in handling glycide.

Example 1a The reaction vessel employed was a stainless steel autoclave with the usual devices for heatautoclave 373 grams of tripentaerythritol along with 365 grams of solvent. In this instance xylene was used. Any nonvolatile inert solvent,

by the reaction as rapidly as added.

The oxide was run in so that the rate of absorption was approximately 20 grams per minute. The temperature range was controlled within 150 to 200 C. and the pressure did not go in excess of pounds at any time except, perhaps, momentarily reaching to pounds. The total amount of ethylene oxide added was 1100 grams. This experiment was included in the table which follows. In some instances the ethylene oxide was added batchwise, hence the pressure developed at times to 200 or 300 pounds gauge pressure.

The same procedure was followed in other experiments except that two larger autoclaves were used in the subsequent experiments, to wit, a 10- liter autoclave and also a 5-gallon autoclave. The working arrangement on this larger auto clave was the same as in the small one but the rate of ethylene oxide addition could be speeded up distinctly, for instance, when using a 10-liter autoclave ethylene oxide was introduced at the rate of 30 to 40 grams per minute, and in the larger autoclave at the rate of approximately 1 to 2 pounds, or about 450 to 1,000 grams, per minute. Since the larger autoclaves were more same as in larger autoclaves possibly the stirred design gives more effective mixture. These are obvious variations which take place in any con- 11 ventional autoclave with a stirrer. It would be immaterial, of course, if the ethylene oxide had been added more slowly except that a greater period of time would have been involved.

equipment as an autoclave. However, since the glycide is generally more reactive than the ethyl ene oxide there does not appear to be any advantage in such particular procedure and in instances where both ethylene oxide and glycide E m e ma pl 4a were employed the procedure has been conducted o that experiments 20 3a are emitted both ways, i. e., adding the glycide first and then r the reason t t they pp i the table and the ethylene oxide, or the other way around, that this example is mcluded because it is the first one adding t ethylene id first, and then the of the series shown in the table obtained by using g1ycide N dles t ay, the oxyethylated chain glyelde yintroduced into the polypentaerythritol mole- The same piece of equipment wa u as P cule must necessarily vary depending on whether V y described, 1. 8., an e v although in the glycide was added first or the ethylene oxthe instant experiment involving the use of glycide m In any t, th final product must be there w no pressure involved and certain 15 obviously water-solvent in a manner entirely difehanges W made as neted subseqnentiy- The rerentiated from the initial reactant. In the autoclave Was q pp With a Water-Cooled table the molecular weight, of course, is an averdenser Which Was shut O When used as an auteage molecular weight based on the assumption (Have. t Was a o eqiJ- pp With a separatefy that the reaction goes,to completion between the llnne d an equallzlng pressure tube 50 that initial raw material and the oxyalkylating agent. q such as ye d Could e f Continuously An attempt was made to obtain a pure decapenat a drop-wise or a faster rate into the vessel and taerythritol by reaction between two m01es of th rat was nt l d y visual examinationpenta-pentaerythritol. The exact composition For eonvemence, this Piece of equipment 13 of this derivative is not known but soluble prodferred to as an autoclave because it was designed ucts were derived which apparently had a molecessentially f such use t it is be noted ular weight, on the basis aforementioned, of ap It Was not so s When eiyelde was employed es proximately 20,000. Needless to say, one need not t y e e O stop with initial water-solubility but there could There Were charged mto the autoclave the e be some enhanced water-solubility over the minireactants (intermediate, solvent, and sodium mum point by merely further oxyalkylating with methylate) as in i P The auteeleve ethylene oxide or glycide, or both. For this reason was l swept Wlth mtrogen e and Surfing in the specification the molecular weight of the Started lmmedla'tely and heat apphed- The intermediate has been set within a range of over perature was allowed to rise to 120 C. The gly- 1,200 to 2590 Gide empl y d; Was eempal'ativeiy D 1359 In regard to the speed of reaction, temperature grams of glymde were Th1s was charged of reaction and reaction pressures (in the case upper reservon: VeSS e1 whlch had been of ethylene oxide or propylene oxide) attention preflously flushed out Wlth mtrogen and was "fi is directed to the fact that the amount of cataequlvalent of sepemtory funnel; The glyfnde lyst used is rather significant. It is usually prac- Was started Slowly mm the t'eactlon mass m tical to start a reaction with one, two or three dmpWPSe The reactlon Started to take per cent of an alkaline catalyst, such as sodium lmmedlatfly the temperature rose methylate, based on the amount of reaction. Subg fi i g g 1 g g g fi g gg ig; sequently if the reaction slows down or takes too rqug a high a temperature, or pressures appear to be addition of glycide was controlled within the d 1 h robabl indicates that more can) range roughly of 0. to C. The addition d X t 2 was continuous within the limitations and all 1 5 e a e numerfmsfns ances the glycide was added in less than 2 hours. This fatalyst Started at the begmnng of the reaction took place at atmospheric pressure with actlon and at the 121991 Silage probzjibly P more simply a small stream of nitrogen passing into 50 than /4% /s% is p s w c is u ually the autoclave at the very top and passing out enough but, as has been pointed m Ban be through the open condenser so as to avoid any added at an intermediate stage. possible entrance of air. The intermediate products obtained in the TABLE A v1 1 M Molar Molar ii ti 68, 1 1 Ratio Glyc1de Ratio, Total Final Emlmm mo to Added, Glyc1d0 Alkylene st Formula Hydrox- Gms. to Hy- Oxide to of ggg yl droiyl Hydro mediate It is believed that one could add a mixture of ethylene oxide and glycide under the same condimanner above described are invariably xylene-insoluble but show a distinct tendency to disperse or tions as ethylene oxide is added, i. e., using the 75 become soluble in water. At times the solubility in water approximates starch solution; although this characterization is approximate there is absolutely no confusion with the insolubility of the original polypentaerythritol used as the raw material. Even if ground to a fine mesh, for instance, 200 mesh, or finer, and shaken in water they simply represent coarse suspensions and nothing more. The product obtained as an intermediate contains solvent which can be readily removed by vacuum distillation. If the solvent happens to be xylene as in the previous examples a temperature of 180 to 200 C. is perfectly satisfactory. During this initial stage the products seem to darken and the intermediate is usually a viscous; somewhat sirupy product of out of the question, there is still discolorization, probably due to the inherent nature of the initial raw material or a subsequent carmelization-like reaction.

Intermediates can be decolorized in the usual manner by treating with charcoal, filtering clay, or the like. generally more desirable to use it after the final stage, e., after the oxypropylation has been completed. No such refinement was employed in connection with the above samples.

PART 3 This section is concerned with the oxypropylation of the intermediates obtained as described in Part 2 immediately preceding. The equipment, reaction conditions, etc., have been specified already.

In the series of examples noted in the subsequent table it has been found expedient to use more than one size autoclave, that is, a size of about 3 liters, a 2 gallon size, and a 5-gallon size.

Previous reference has been made to the arrangement used when oxyalkylation is conducted with glycide by simply changing the position of the reflux condenser or some other suitable trap arrangement so the xylene employed as a solvent can be readily removed. For convenience, in the subsequent experiments the xylene was removed although this is unnecessary for reasons above indicated unless required by ultimate use of the final product. In experiments noted in the table approximately one-tenth of a gram molecular weight was taken i. e., the intermediate described in Part 2, preceding. The amount of propylene oxide added in each instance was approximately moles, or 575-585 grams. Since this was added to onetenth of a gram molecular weight equivalent the ratio is the same as if 100 moles of propylene oxide were added per gram molecular weight of the in termediate.

For convenience, in Table B there is also noted the molal ratio of propylene oxide to other alkylene oxide based on the hydroxyl number of the initial reactant, i. e., the polypentaerythritol initially employed. It will be noted that the table shows molecular weight variations ranging from 7,000 to approximately 54,000. All the products were xylene-soluble.

Oxypropylation of the intermediate sometimes yields products which show considerably decreased water solubility and sometimes even seem to approach water insolubility, but no attempt has as the initial starting weight,

If such procedure is employed it is been made to define this being markedly different than the water solubility of the intermediate. There is, of course, an enormous difference between the water-solubility of the initial raw material, i. e., the polypentaeryth ritol which, in fact, is not water-soluble at all.

The amount of catalyst employed'is noted in grams. Generally speaking, approximately 2 to 3% by weight of sodium methylate was added to the initial charge, i. e., the intermediate obtained as described in Part 2. Whenever the amount of catalyst fell below one-half of one per cent, more was added.

It will be noted that the amount of catalyst actually present is higher than indicated by the figures for the reason that there is residual catalyst left over from the intermediate step in Part 2.

The temperatures, pressure, and time of reaction have been indicated previously in Part 2 for the reason that the same equipment is used in oxypropylation as in oxyethylation. In the use of the small autoclave approximately grams of propylene oxide were added per minute; in the use of the larger autoclave (2 gallon size) the rate was increased to approximately to grams per minute; in the largest autoclave (5 gallons) about 300 to 700 grams of propylene oxide were added per minute.

As has been pointed out previously, the rate of reaction, the pressures, and temperatures, all are related to the time required for reaction and'un der the conditions previously indicated the amount of catalyst used above is more than ample for perfectly satisfactory working conditions, for example, temperature, pressures, etc., as indicated in Part 2 in connection with oxyalkylation as herein described.

There is, however, a factor which enters into oxypropylation in this series of experiments which is not obvious or significant in Part 2 and that is the size of the molecule. The reaction obviously must take place at the terminal hydroxyl. If one starts, for example, with heptapolypentaerythritol having 16 hydroxyls and oxyethylates as described in Part 2, and then oxypropylates, it becomes obvious that there are present and susceptible to reaction 16 hydroxyl groups per molecule and no more. As the molecule grows larger the opportunity for reaction by random collision decreases. Ordinarily, this may not be a factor but I have noticed that as one passes the 20,000 molecular weight range, and particularly the range between 20,000 and 50,000, adding catalyst is much less effective than in the lower molecular weight range. In other words, the reaction cannot be speeded up necessarily to any great degree by increasing the amount of catalyst from to 1 A; The reaction apparently is slow due to the size of the molecule. Needless to say, this View is in the nature of speculation and may be entirely Wrong. Such delayed activity may reside with some other cause. However, from a practical standpoint no advantage has been found and derivatives much beyond a 50,000 molecular weight based on a statistical average and completeness of reaction are not justified in light of cost. For reasons of exploration some have been made in the 100,000 molecular weight range but the slowness of reaction places this type at a disadvantage in light of the increased cost of manufacture. If glycide is used in the intermediate stage additional hydroxyl radicals are formed and, presumably, the secondary hydroxyls are as reactive as the primary hydroxyls. This effect particular solubility as manipulative procedure is more costly.

TABLE B 16" specified p'olypentaerythritols or thereof which to the polypentaerythritols, are water-insoluble materials. They are water-insoluble and xylenemodifications Molar Ratio, Pro- 31 2?? 51:91:; Catalyst Molar Wt Alk lene (Sodium of Reac- Xylene ozme Methyl Soluble e) Based on Original Hydroxyl Group 10 4. 2 Yes 10 8. 3 Yes 10 12. 5 Yes 10 16. 7 Yes 10 20. 8 Yes 10 2. 2 Yes 10 4. 4 Yes 10 6. 7 Yes 10 8. 9 Yes 10 ll. 1 Yes. 10 13.3 Yes. 10 .7 Yes 10 1. 39 Yes 10 2.07 Yes. 10 2. 78 Yes 10 3. 47 Yes 1 10- 4. 19 Yes. 10 4. 85 Yes. l8 5. 56 ges '7 cs 10 l. 39 Yes 10 2. 07 %es 2. 78 cs 10 3. 47 Yes 1 l0 4. 19 Yes l 10 4. 85 Yes 1 10 7 Yes 10 1.39 Yes 10 2. 07 Yes lg 2. "i8 gee 3. 7 es. 10 4. 19 520 Yes. 10 4. 85 320 Yes. l0 5. 56 54, 120 Yes.

! Denotes colloidal water solubility.

In the preparation of the above compounds practically without exception when the molecular weight reaches 35,000 or more the products give an excellent colloidal solution in water comparable, in fact, with an ordinary soap solution in many ways. For instance, such characteristic solubility is shown very clearly by compound Example lfib, which can be prepared entirely from commercially available chemical products, i. e., hepta-pentaerythritol, ethylene oxide and propylene oxide.

My preferred final products are those which show at least colloidal solubility as illustrated by Example 161) as far as synergistic or emulsion promoting properties are concerned. However, for demulsification I prefer lower molecular weights, in the range of approximately 20,000 to 25,000.

The products above described are viscous amber colored liquids which, in fact, are similar to those derived at the intermediate stage. The color varies from deep yellow or light amber to amber, dark amber, or reddish amber. The viscosity varies somewhat from that of *castor oil to that of blown castor oil. The products can be bleached in the customary manner by use of charcoal, filter clays, or the like. If a solvent is used initially with a polypentaerythritol to give a slurry which is convenient to handle, such solvent can remain in the final product or be removed by vacuum distillation. However, my preference is, if desirable to remove the solvent, to do so at the end of the intermediate stage.

It is obvious that certain modifications can be made which do not depart from the spirit of the invention. The initial raw materials, 1. e., the

Such initial reactants are treated in the manner described to yield materials which are water-dispersible or in which the water-solubility is at least completely differentiated from that of the original products. At this stage the intermediates are still xylene-insoluble. They are then converted into xylene-soluble materials. It is perfectly obvious that if one treats a material as described in the first table with ethylene oxide or glycide or a combination, that a small percentage of the oxide could be replaced by another oxide, as for example, propylene oxide. For instance, note that one of the initial materials, for instance, Examples 9a, has a molecular weight of approximately 7200. In the introduction of approximately 144 moles of ethylene oxide a few of such moles of ethylene oxide could be replaced at an earlier intermediate stage with propylene oxide without particularly affecting the specified characteristics. Needless to say, such variation would not be departing from the spirit of the invention in the slightest.

Likewise, Example 9a is oxypropylated subsequently to give Examples 12b, 13b, 14b, etc. Example 1473 has a molecular weight of about 25,000. It goes without saying that a mole or two of ethylene oxide, or a mole or two of glycide, could be used in course of such procedure without particularly affecting the characteristic properties of the product. Here, again, such minor variation does not represent departure from the spirit of the invention.

If one examines the previous tables it becomes evident that the original insoluble constituent, i. e., the polypentaerythritol, such as tripentaerythritol, may contribute as little as 1% or less,

insoluble materials.

bear a simple genetic relationship I 7 of the final product. For instance, in Example 111 tripentaerythritol was treated with ethylene oxide so as to increase the molecular weight from 372 to 1470.

In the series of experiments beginning with lb through b, a product Was obtained whose molecular weight was approximately 30,000. Obviously had this example, i. e., 5b, been taken one stage further the percentage contributed by the original tri-pentaerythritol would have been under 1%. The upper range is approximately 7%, i. e., the initial reactant contributes from a fraction of 1% up to 5%, 6% or 7% of the final end product.

It is also to be noted that the general range of preferred examples shows that the alkylene oxide added in the preparation of the intermediate is within the range roughly of 3 to 1 to 9 to l, or in some instances 12 to 1. Likewise, the amount of Actually from a practical standpoint there is no reason why the water-solubility step and the Example 35b tional in ature modestly above to wit, in the neighborhood of about 240 C. 13.25 oxide were added, about, roughly 1.3 times the weight of the initial tri- This oxyethylation was conducted at a temperature of 240 to 255 the pressure regulator set for series the temnot too much above The 13 pounds of a little less than an perature was 245-255 F., the boiling point of water. ethylene oxide were added in hour.

present. In other the amount of ethylene oxide at this Stag usin up to twice the weight, for example, based on the original polypentaerythritol employed.

constant, to wit, 48.2% ethylether and 51.8% to solvent means this of diethyleneglycol dixylene hereafter reference specific mixture.

49.13 pounds of the reaction mass previously identified as Example 35?) and equivalent to 6.38 pounds of tripentaerythritol, 8.14 pounds of The time required to add the was 4.25 hours. The oxide was added at the rate of about 5 pounds per hour.

the two preceding examples. The amount of propylene oxide added was 24.5 required to add the oxide was Example 381; 46.88 pounds of the reaction mass identified as Example 37b immediately preceding and equivalent to 2.99 pounds add the propylene oxide was 5 hours.

subjected to further oxypropylation as in Example 3922, following.

19 Example 3% 42.13 pounds of reaction mass identified as Example 381) preceding, and equivalent to 2.05 pounds of tripentaerythritol, 2.54 pounds of 20 Example 35b was iemulsiiiable in water, andxinsoluble in both :xylene and kerosene; Examples 36b through 3% were ,all insoluble in water, dispersible in xylene,and insoluble in kerosene; Ex-

ethylene oxide, 34.60 pounds of propylene oxide, 5 ample W m in Water Soluble m :9 pound of caustic soda, and 2.75 pounds of lens, Q W m kemsene? and Exampm solvent 'were subjected to further oxypropylat'i-on 'msmuble Water soluble m both with 14 pounds of propylene oxide. The cond'i- Xylene and kemsenetions of reaction were the same as described in The final pmd-uct's irom aflhght Straw the fourpreceding examples. The time required color 9 s t vlscous e to add'the oxide was 1 1 hours The oxide was of a reddish brown color in a few instances. This added at about w rate of 3 pounds per a was-more oriless thecharacteristic of all the oxy- When the reaction was complete part of the repmpylatedipmducts at the f f These action mass w'th withdrawn and subjected to P 3 were, 01: 2P01-11se,-sl1ghtly alkaline due to further oxyprop lation as described in Example 15 the tresldual-caustic soda. The residual basicity, 40b, immediately following due to .the catalyst, of course, would be the same as if sodium. methylate had been used. Example 40?) speaking 'of insolubil-ity in water or solubility 14 p ds i" h e i n ma identified as in kerosene such solubility test can be made sim- Example 39b, immediately preceding, and equivap yby shaking small .amounts of the materials in lent to 1.36 pounds of tripentaerythrito'l, 1:69 a test tube with-water, for instance, using 1% to pounds of ethylene oxide, 32.36 pounds of propyl- 5 approximately based on the amount of water ene oxide, .13 pond of caustic soda, and 1.84 present. pounds of solvent, were subjected to further oxy- Needless :to say, there is no complete converpropylation with 13.75 pounds of propylene oxide. sion of propylene oxide into the desired hydrox- The time required toadd this propylene oxide was mated-compounds. is indicated by the fact 6 hours. The oxypropylation was conducted in that the theoretical molecular weight .based on a the same manner as described in the five examstatistical average is greater than the molecular ples immediately-preceding. The oxide was added weight calculated .by usual methods on basis of at the rate of approximately 2 to 3,pounds per acetylor hydroxyl Walue. Actually, there is no hour. At the end of the reaction period part completely satisfactory method for determining of the reaction mass was withdrawn and the remolecular weights of these types .or compounds mainder subjected to afmal oxypropylation step with a high degree of accuracy when the moas described in Example 411), following. lecular weights exceed 2,000. In some instances Example 41b the acetyl valueor hydroxyl value serves as satisfactorily as an index to the molecular weight as 43.83 pounds of the reactlon mass identified as any .otherpmcedum, Subject tome above 1mm Example 401) 'precedmaend e-qlllvfilent tations, and especially in the higher molecular pounds 9 xnpemaerythmtol '4 pounds 9 weight range. anydifiiculty is encountered in ylene oxide 39I55POundS'OfpIOPY1eDe made 49 the manufacture or the esters as described in pound of faustmfioda and s f m =4 thetstoich'ometrical amount of acid or were sublected to finajl OXYPIOPYIaPOn m the acid compound should :be taken which corresame manner as descnbed m F SIX examples spondstothe indicated :acetyl .or hydroxyl value. precedmg, h9 amounfi of oxlde add d w 11 This matter has been discussed in the literature g fi T time a 93 r and is a matter of common knowledge and. reours t was d? m rate 9 about 1 /2 quiresxno further elaboration. In fact, it is ilpounds per hour. It lS'llO be noted that no catalustmted by some of the examples appearing in lyst was added in any of the examples after Exthe patent previously mentioned ample 3517, i. e., no further catalyst was added in Examples 361) through 4112, inclusive. 1 ART 4 What has been said preceding is presented tabular form in Table '1, following, with some As previously pointed out the present invention added information as to molecular weight and as isconcerned with acidicesters obtained from the to solubility of the reaction product in water, oxypropylated derivatives described in Part 3, xylene, and. kerosene. immediately preceding, and polycarboxy acids,

TABLE 1 Composition Before Composition at End Max. a The Them 3. c. Oxide hrs. M. w. fig" 1n.

2,440 15-20 5%? 5,295 15-20 5 7,210 15-20 5 19,650 5- 13, 470 15 20 e 16, cm 15-20 8 1 Solvent-=diethyleneg1ycol diethylether=48.2%; xylene-=51.8%. E means ethylene oxide.

P means propylene oxide.

21' 22 particularly tricarboxylic acids like citric and (11- the oxypropylated derivatives described n Pa t 3 xy acids u h as ad p a d, phthali a id, is then diluted further with sufiicicnt xylene r a yd u c c diglycollic acid, decalin, petroleum solvent, or the like, so that acic acid, azelaic acid, aconitric acid, maleic acid one has btained approximately a 40% solu ion. or anhydride, citraconic acid or anhydride, ma- 5 To this solution there is added a polycarboxylleic acid or anhydride adducts as obtained by ated reactant as previously described such as the Diels-Alder reac io from Products Such as phthalic anhydride, succinic acid or anhydride,

ma ei anhydr d nd y p n Such diglycollic acid, etc. Themixture is refluxed until acids sh uld e at t l s t y a n esterification is complete as indicated by elimimpos d durin rifi i n- Th y y connation of water or drop in carboxyl value. Needwill s y as 36 carbon atoms as, for exampl less to say, if one produces a half-ester from an the acids obtained by dimerization of unsaturatanhydride such as hthali nhydrid n water ed fatty a id, uns turat d m n y fatty is eliminated. However, if it is obtained from acids, or unsaturated monocarboxy acids having diglycollic acid, for example, water is eliminated.

18 carbon atoms. Reference to the acid in the 1 All such procedures were conventional and have h t pp d d c aims v us y n ud s t been so thoroughly described in the literature ydrides or any other obvio q iv n M that further consideration will be limited to a few preference, however, is to use polycarboxy acids examples and a comprehensive table.

having not over 8 carbon atoms. Other procedures for eliminating the basic The production of esters including acid esters 20 residuai catalyst, if any, can be employed. For (fractional esters) from polycarboxy acids and example, the oxyalkylation can be conducted in yc s or o er hydroxyl ted compounds is well absence of a solvent or the solvent removed after known. Needless to say, various compounds may oxypropylation. Such oxypropylation end prod be used such as the low molal ester, the anhynot can then be acidified with just enough condride, the acyl chloride, etc. However, for purcentrated hydrochloric acid to just neutralize the pose of economy it is customary to use either the residual basic catalyst. To this product one can .acid or the anhydride. A conventional procedure then dd a small amount of anhydrous sodium is employed. On a laboratory scale one can emsulfate (sufficient in quantity to take up any ploy a resin pot of the kind described in U. S. water that is present) and then subject the mass Patent d d March 1950, o to centrifugal force so as to eliminate the hy- De Groote and Keiser, and particularly With one drated sodium sulfate and probably the sodium more opening to permit the use of a porous chloride formed. The clear somewhat viscous Spreader if hydrochloride m d a is to be used straw-colored or amber liquid so obtained may asacatalyst. S uch device or absorption spreader contain a small amount of sodium sulfate or consists of minute Alundum thimbles which are sodium chloride but, in any event, is perfectly connected to a glass tube. One can add a sulacceptable for esterification in the manner defonic acid such as paratoluene sulfonic acid as a scribed. catalyst. There is some objection to this because It is to be pointed out that the products here in some instances there is some evidence that described are not polyesters 1n the sense that this acid catalyst tends to decompose or rear- 0 there is a plurality of both polypentaerythritol range heat-oxypropy1ated compounds, and parradicals and acid radicals; the product is charticularly likely to do so if the esterification temacterized by having only one polypentaerythritol perature is too high. In the case of polycarboxy radical.

acids such as diglycollic acid, which is strongly By following slight modifications of what has acidic there is no need to add any catalyst. The I been said previously one can conduct the esterifiuse of hydrochloric acid gas has one advantage cation on a laboratory scale with greater conover paratoluene sulfonic acid and. that is that venience. Obviously, if one starts with a polyan exceedingly slow rate so as to keep the rethan intermediate or complete cross-linking, and action mass acidic. Only a trace of acid need be also the fact that there are certain limitations present. I have employed hydrochloric acid gas as far as solubility goes in any large molecule, to or the aqueous acid itself to eliminate the initial say nothing of peculiarities of structure insofar basic material. My preference, however, is to that one of the original reactants, for instance, use no catalyst whatsoever. dipentaerythritol or tripentaerythritol, are much The products obtained in Part 3 pre g may less soluble in water than one might ordinarily contain a basic catalyst. As a general procedure xpect on the carbon oxygen m After the I have added an amount 0f half-Concentrated water is removed in the case of the esterification With the Xylene present 11nt11 the Water can be soluble in such nonpolar solvent, and possibly separated by a phase-separating trap. As Soon because it either does cross-link or at least gives 7 as the product is substantially free from water a pseudo gel. I have used the terminology the distillation stops. This preliminary step can pseudo for the reason that such gel is be carried out in the flask to be used for esterifiversible as distinguished from a true non-r cation. If there s a y further depOSitiOn 0f versible gel produced by cross-linking. The exact sodium chloride during the reflux stage needless I nature of this tendency to become insoluble or to say a second filtration may be required. In any tendency toward gelation is obscure and not fully event the neutral or slightly acidic solution of understood. In light of the eflect of semi-polar i solvents'there'rmay :be some relationship, and in fact an important one to hydrogen bonding factors.

However, by the addition-of a semi-polar solvent, such as diethyl carbitol, which is the trade name for diethyleneglycol diethylether, or some other similar solventssuchras an alcohol, one tends to reduce or eliminate this effect. The alcohol, of course, must be'added at the end of the reaction so as to not interfere with the esterification. The non-hydroxy semi-polar solvent can be obtained at the start ofesterification provided itdo'es not interfere with water removal. In any event, one can obtain a homogeneous system in which substantially the entire material is solid.

Referring .to the original 'oxypropylation it is to be noted that a solvent,-such'as'xylene, is present for a matter of convenience such as giving an incipient "slurry. Also, it is to be noted that the intermediates are xylene-soluble especially in the latterstages. Therefore, even if one were to use benzene alone or cymene alone, there still would be present thexylene which had been used in the oxypropylation step.

Referring now to a number of examples, for instance, Examples .10. through 420, with the exception of 50, 11c, 35c and 40a; in these particular instances, as explained subsequently, a small amount of methanol was used after esterification was complete to give a more satisfactory solution. The xylene indicated is not added xylene but refers to :xylene used along with 'diethyleneglycol d-iethylether in the original oxypropylation step. Subsequently, however, more diethyleneglycol diethylether was added. In each instance the amount of benzene added was 50 grams Then sufiicient diethyl carbitol was added to give the indicated :amou-n-t ofsol tion except in a few instances when methanol was added as previously referred to :and as will-be explained later. Diethyl carbitol is the trade name for diethyleneglycol idiethylether as manufactured :by Carbide iz Carbon Chemicals Corporation; New York city, N. Actually, the :amountof this latter solvent used wasjudge'dpurel'yias a matter of convenience in theglassware employed and when the reaction was complete the reaction'mass was withdrawn and this weight used .to calculate the actual total solvent. In :each instance an effort was made to obtain approximately a solution.

The selection of 50,'% solvent was just arbitrary for the reason that when these -fcompounds were tested for dem 'ification it was convenient to have a 50% solution. 'It'goe's without saying that a 25% solution wouldserve also. In practically every instance .after .a. homogeneous solution was obtained "one could -subject it to 'distil1ation,;particularly vacuum distillation, remove asmall amount of benzene and Still have a homogeneous solution havingexact'ly 50% if desired. In this modification one could, of course, use decalin, cymene, or some other ether such as the diethyl ether of eth .lenegl'ycol, or a comparable ether instead-of the particular one used.

In Examples 50, 11c, 35c and 400 previously referred to there is a tendency for solids to separate out. In these experiments there was some solid material at the end of the procedure which was apparently soluble in methanol. Therefore, a small amount of methanol, approximately 10 to 30 grams, was added which resulted in more complete solubility. In any event in some instances the final solution contained less than 50% active material, i. e., more than 50% solvent, and this is noted. All these variations are of incidental value as a convenience but not an inherent part of the invention. a This is obvious from the hereto attached claims.

The data included in the subsequent tables, 1. e., Tables 2 and 3, are self-explanatory and very complete, and it is believed no further elaboration is necessary.

TABLE 2 Amt. of

. Amt. bf

' Actual Polycar- Hydmwl Hydroxyl Polycarboxy Reactan boxy Re- .(gm) actant 88. 3 Diglycolic Acid. 42. 9

3 88.3 'Oxalic Acid- 40. 3 88. 3 Aconitic Acid 55.7

88. 3 Adipic Acid. 46. 7

88. 3 lhthalic Anhyd 47. 4

88. 3 Malcic AnhytL- 31. 4

5 113. 2 Diglycolic Acid 42. 9 113.2 Oxalic Acid 40.3

113. 2 Aconitic Acid 55.7

113. 2 Adipic Acid" 46. 7

113.2 Phthalic A1111 47.4

113. 2 Maleic Anh 31. 4

112 Aconitic A01 44. 5

112 Adipic Acid... 37. 4

112 fhthalic Anhyd. 36.7

112 Maleic Anhyd. 24. 4

129 Diglycol-ic Acid. 32. 2

129 Oxalic Acid 30. 2

129 Aconitic Acid. 41. 8

129 Adiplc Ac 35.1

TABLE 3 Max. Amt. Ester- Solvent ification (era) Time of Esterification (hrs) Water Out (cc.)

Percent Solvent S 01v em 1 5. 9 50. 2% 18. 6 52. 30-- 1% 6. 50. 4a.- 1 5. 8 50. 5c Benzene, Xylene, Diethyl 3 1. 4 50. methanol. 6c Benzene, Xylene, Diethylcarbitol 2 2. 0 62. 7c -.do 6. 0 50. 8c 2 17. 6 50. 9c 1 6. 0 50, do 1 6. 0 50. Benzene, l 1% 0. 8 50.

Methanol. 120 Benz 1% 0. 6 50. 2 4. 6 54. 2 14. 2 63. 2 7. 0 53. 2 8. 2 53. 3 2. 0 53. 3 1. 0 53. 2. 6 50. c 12. 9 50. 4. 2 50. 3. 8 50. 50. 50.

UIOI 993.

Bezene, Xylene, D 134. 5

methanol.

enzene, xylene, Diethylcarbitol,

methanol.

Benene, xylene, Diethylcarbitol The procedure for manufacturing the esters has propylene oxide or derivatives thereof, i. e., of an been illustrated by preceding examples. If for aldehyde, ketone, or ally] alcohol. In some inany reason reaction does not take place in a stances an attempt to react the stoichiometric manner that is acceptable, attention should be amount of apolycarboxy acid with the oxypropyldirected to the following details: (a) Recheck the ated derivative results in an excess of the caruse a stoichiometrically equivalent amount of droxy radicals are present then indicated by the acid; (b) if the reaction does not proceed with hydroxyl value. Under such circumstances there reasonable speed either raise the temperature inis simply a residue of the carboxylic reactant or 16 hours if need be; (c) if necessary, use the esterification procedure can be repeated using of paratoluene sulfonic acid or some other acid an appropriately reduced ratio of carboxylic reas a catalyst; (d) if the esterification does not actant.

produce a clear product a check should be made Even the determination of the hydroxyl value experimentation and can be removed by filtering ence of any inorganic salts or propylene oxide Everything else being equal as the size of the Obviously this oxide should be eliminated. molecule increases and the reactive hydroxyl rad- The solvent employed, if any, can be removed complete esterification. or liquids are generally from pale amber to 21.

Even under the most carefully controlled convery pale straw color, and some have a distinct ditions of oxypropylation involving comparatively reddish-brown color and show moderate viscosity, low mp rature and n tim of r c ion her or sometimes increased viscosity in light of what are formed certa C p u W os O D S has been said previously in regard to cross-linktions is still obscure. Such side reaction proding, gelation, etc. Unless there is some reason to 110138 can contribute a substantial proportion 0f do otherwise my preference is to handle these the final CO e riO eac iO mixture. Various esters as 50% solutions in suitable solvents. They the appearance of a vinyl radical, or isomers of and decolorization is not justified.

21 PART 5 As pointed out previously the final product obtained is a fractional ester having free care. boxyl radicals. Such product can be used as intermediate for conversion into other deriva-.- tives which are effective for various purposes, such as the breaking of petroleum emulsions of the kind herein described. For instance, such product can be neutralized with an amine so. as to increase its water-solubility such as triethanolami-ne, tripropanolamine, oxyethylated triethanolamine, e Similarly, such product can be neutralized With some amine which tends to reduce the water-solubility su as cyclohexylamine, benzylamine, decylamine, tetradecylamine, octadecylamine, etc. 'Furthermoi'e, the residual carboxyl radicals can beesterified with alcohols, such as low molal alcohols, methyl, ethyl, propyl, butyl, etc., and also high molal alcohols, such as octyl, decyl, cyclohexanol, octadecyl alcohol; etc. Such poses due to their modified solubility- Thisis particularly true where surface-active. materials are of value and especially in demulsification of water-in-oil emulsion.

Having thus described my invention, what I claim as new and desire to; secure. by Letters Patent, is:

1. An ester of a polycarboxy acid and a polyhydroxy compound in which theratio of polycarboxy acid to polyhydroxy compound is one mole of the acid for each available. hydroxyl radical of the polyhydroxy compound and, in which the polyhydroxy compound is; an oxypropylated oxyalkylated polypentaerythritol, in

'oxypropylated oxyalkylated polypentaerythritol has a molecular weight in the range of 5,000 to 100,000 on. anaverage statistical basis and. the

= p l n ae v hrt tg re r s nts, n t more than '7 byzw i ht thereof, on the assumption of complete reaction involving the alkylene oxides and the poly-pentaerythritol andin which the poly? carbo-xy. acid is selected from the group consisting of; acyclic and isocyclic polycarboxy. acids having not more than 3,,carboxy. groupsand cornposed or carbon, hydrogen and oxygen and having not more than 8 carbon atoms.

2. The product of claim. 1 wherein the polypentaerytliritol has at least 2 and not more than 3- pentaerythritol radicals.

3. The product t claim 2 wherein the polycarboxyacid is a dicarboxyacid.

T e. p uc i. cl r n h c earboxy acid is phthalic acid.

5. The p ductoi. c aim. 3, wher in. the disarboxy acid is maleic acid.

6. The product of claim 3 wherein the; dicar-w boxy acid is succinic acid.

I. .7. Theiproduct ofclaim. 3. wherein the..dicarboxy acid is citraconic acid;

8. Theproductof. claim 3 wherein the d102,]?!

o ac dds d glypflllis asi No references cited. 

1. AN ESTER OF A POLYCARBOXY ACID AND A POLYHYDROXY COMPOUND IN WHICH THE RATIO OF POLYCARBOXY ACID TO POLYHYDROXY COMPOUND IS ONE MOLE OF THE ACID FOR EACH AVAILABLE HYDROXYL RADICAL OF THE POLYHYDROXY COMPOUND AND IN WHICH THE POLYHYDROXY COMPOUND IS AN OXYPROPYLATED OXYALKYLATED POLYPENTAERYTHRITOL, IN WHICH THE OXYALKYLATED POLYPENTAERYTHRITOL HAS A MOLECULAR WEIGHT IN EXCESS OF 1200 AND LESS THAN 25.000 IS A POLYPENTAERYTHRITOL LINKED TO RADICALS OF THE CLASS CONSISTING OF ETHYLENE AND RADICAL OF THE CLASS CONSISTING OF ETHYLENE AND HYDROXY PROYLENE RADICALS, AND IN WHICH THE OXYPROPYLATED OXYALKYLATED POLYPENTAERYTHRITOL HAS A MOLECULAR WEIGHT IN THE RANGE OF 5,000 TO 100,000 ON AN AVERAGE STATISTICAL BASIS AND THE POLYPENTAERYTHRITOL REPRESENTS NOT MORE THAN 7% BY WEIGHT THEREOF, ON THE ASSUMPTION OF COMPLETE REACTION INVOLVING THE ALKYLENE OXIDES AND THE POLYPENTAERYTHRITOL AND IN WHICH THE POLYCARBOXY ACID IS SELECTED FROM THE GROUP CONSISTING OF ACYCLIC AND ISOCYCLIC POLYCARBOXY ACIDS HAVING NOT MORE THAN 3 CARBOXY GROUPS AND COMPOSED OF CARBON, HYDROGEN AND OXYGEN AND HAVING NOT MORE THAN 8 CARBON ATOMS. 